Many investigations on 2-anilinopyrimidine derivatives have heretofore been made, and some compounds are known to have activity chiefly in the field of fungicides. For instance, East German Patent No. 151,404 describes that 2-anilinopyrimidine derivatives represented by the general formula ##STR2## wherein R.sup.2 and R.sup.3 independently represent a hydrogen atom, an alkyl group which may be substituted, an aryl group, an aralkyl group, a halogen atom, a hydroxy group, an alkoxy group, an aryloxy group, a mercapto group, an alkylthio group, a carboxy group, an alkoxycarbonyl group, a carbamoyl group, a cyano group, a cyanato group, an isocyanato group, a thiocyanato group, an isothiocyanato group, a sulfo group, a halogenosulfonyl group, an amino group which may be substituted, a nitro group, or an acetyl group which may be substituted, and R.sup.4 and R.sup.5 represent a hydrogen atom or an alkyl group, have a fungicidal activity. Also, British Patent No. 1,245,085 discloses the fungicidal activity of pyrimidine derivatives represented by the general formula ##STR3## wherein A and A.sup.1 represent a hydrogen atom, a nitro group, an amino group, a halogen atom, a hydrocarbon group or hydrocarbon groups which may be substituted, R.sup.6 and R.sup.7 represent a hydrogen atom or organic groups, and A.sup.2 represents a halogen atom.
These conventional compounds are, however, found to have defects that their fungicidal activity is weak, and moreover their anti-microbial spectrum is narrow.